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Cambio entre el dímero supramolecular y el autoensamblaje supramolecular no roscado de

Kazuhiro Yamauchi¹, Yoshinori Takashima, Akihito Hashidzume

¹Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.

Journal of the American Chemical Society

|March 14, 2008

Resumen

La fotoirradicación controla los conjuntos supramoleculares. Los dimeros 3-trans-estileno amida-alfa-ciclodextrina (3-trans-Sti-alfa-CD) se transforman en estructuras no roscadas tras la fotoisomerización trans-a-cis en el agua.

Área de la Ciencia:

Se trata de una química supramolecular.
La fotoquímica es la fotoquímica.
Ciencia de los materiales ciencia de los materiales.

Sus antecedentes:

Las ciclodextrinas son conocidas por su capacidad para formar complejos de inclusión.
Los derivados de estilibeno pueden someterse a fotoisomerización, cambiando su geometría y propiedades.
Los conjuntos supramoleculares ofrecen propiedades sintonizables para diversas aplicaciones.

Objetivo del estudio:

Para investigar el comportamiento de autoensamblaje de 3-trans-estileno amida-alfa-ciclodextrina (3-trans-Sti-alfa-CD) en soluciones acuosas.
Para explorar el impacto de la fotoisomerización en la estructura supramolecular de 3-trans-Sti-alfa-CD.
Para determinar si la fotoirradicación puede controlar las transiciones estructurales de estos complejos supramoleculares.

Principales métodos:

Síntesis de 3-trans-estilbeno amida-alfa-ciclodextrina. también conocido como 3-trans-estilbeno.
Análisis espectroscópico (por ejemplo, RMN, UV-Vis) para caracterizar el complejo.
Experimentos de irradiación fotográfica para inducir la isomerización.
Análisis estructural de los ensamblajes supramoleculares resultantes en solución acuosa.

Principales resultados:

3-trans-Sti-alfa-CD forma un dímero de doble hilo en soluciones acuosas.
La fotoisomerización de la fracción de stilbeno de trans a cis induce un cambio estructural.
La estructura supramolecular pasa de un dímero de doble hilo a ensamblajes sin hilo tras la fotoirradicación.
Los cambios estructurales observados son controlables a través de la fotoirradicación.

Conclusiones:

La fotoisomerización de la unidad de stilbeno dentro del complejo 3-trans-Sti-alfa-CD es un factor clave para controlar la arquitectura supramolecular.
La fotoirradicación proporciona un mecanismo para el cambio reversible entre diferentes estructuras supramoleculares.
Estos hallazgos demuestran el potencial de materiales sensibles a la luz basados en conjugados de ciclodextrina-estilbeno.

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